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Erectile Dysfunction Risk May Be Determined By Men's Genes

Researchers have identified a genetic variant that might be the cause of erectile dysfunction in men. The discovery could pave the way for new genetic-based treatments to help patients.

The study titled "Genetic variation in the SIM1 locus is associated with erectile dysfunction" was published in Proceedings of the National Academy of Sciences on Oct. 8.

Impotence is a common problem for men and is also increasingly prevalent with age. In a 2007 study, an estimated 18 million men in the United States were affected. Determining figures is quite challenging as erectile dysfunction (ED) due to unclear diagnostic criteria and underreporting.

The condition is defined as the inability to develop or maintain an erection during sex. While it is normal to experience this now and then, ED is characterized by a regular occurrence which takes its toll on a person's sex life, relationship, and self-image.

The research team identified something known as a "T-risk allele" when examining genetic information. An allele can be described as a variant form of a gene — which, in this case, is a variation near the SIM1 gene.

Eric Jorgenson, the lead author of the study, called it "an exciting discovery" which could lead the way in exploring new therapies that target genetics.

"Identifying this SIM1 locus as a risk factor for erectile dysfunction is a big deal because it provides the long sought-after proof that there is a genetic component to the disease," said Jorgenson, a research scientist at Kaiser Permanente.

Men who had this variant had a 26 percent increased risk of experiencing ED. And men who had two copies of the variant had a 59 percent higher risk, even after accounting for other risk factors.

"We know that there are other risk factors for erectile dysfunction, including smoking, obesity, diabetes, and cardiovascular disease," Jorgenson said. "What is striking about the region in the human genome that we identified is that it acts independently of these known risk factors. That is, this genetic location appears to act specifically on sexual function."

Nearly half of all patients diagnosed with ED do not see their symptoms improve with currently available treatments. If the source of the problem is believed to be psychological (for instance, an anxiety disorder), the doctor may recommend sessions with a licensed therapist.

In other cases, the patient might be prescribed medications or even given the option of surgery. These treatments could include side effects like headaches, muscle pain, and infections.

While scientists conduct further studies on this identified gene, the best way to reduce ED risk is to follow a healthy lifestyle. Getting regular exercise, maintaining a healthy weight, avoiding the use of cigarettes and illegal drugs are some of the steps recommended by the National Institute of Diabetes and Digestive and Kidney Diseases.